The invention relates to a motor vehicle door lock with a body-side latch housing and a hood- or door-side locking bolt or vice versa and with a locking and/or opening device.
The latch housing normally contains a frame box and a latch cover for locking the motor vehicle door lock. The frame box normally contains a locking mechanism comprising a catch and pawl, interacting therewith. The catch and the thus defined motor vehicle door latch interact with the locking bolt in the known manner.
As usual, the latch housing can be arranged on the hood- or door-side. In the first case, the latch housing is fixed on a car body by, for instance, bolting. In the second option, the latch housing and thus also the door lock is fixed on the inside or on a door, a hood or a flap or similar.
Consequently, available latches include side door latches, tailgate latches and hood latches or bonnet latches. All of these latches are covered by the generic term motor vehicle door latch and, when combined with the locking bolt, by the generic term motor vehicle door lock.
According to the invention, the latch housing is normally secured to the body side and is thus arranged on an associated car body. In contrast, the locking bolt is connected to a hood so that the invention refers in most cases to a hood latch or bonnet latch. The arrangement can, however, generally also be the other way around. In this case, the locking pin is connected to the body or motor vehicle body, whilst the latch housing and thus the motor vehicle door latch is secured on the bonnet or generally on the door side.
Practical applications and the generic state of the art according to EP 1 489 252 B1 advantageously contain locking and opening aids, generally ensuring that once a certain preliminary closing position has been reached, the distance between the body and the bonnet or door to be closed is reduced (closing position). This is generally achieved with the aid of a motor or with the aid of a motorized drive, although mechanical locking and opening is also possible and covered by the invention. Furthermore, also opening devices exist, with the aid of which the respective hood or motor vehicle hood or door or motor vehicle door can be opened or opened out in relation to the motor vehicle body. Such locking/opening devices can, generally also be combined.
In general, designs do, however, contain in most cases only one closing aid or closing device, moving for instance a motor vehicle door from the pre-ratchet position to the main ratchet position with the aid of a motor. For this purpose, a rocker is acted upon in the generic state of the art as disclosed in EP 1 489 252 B1. The motorized drive acts on a toggle lever element containing two toggle levers. It is thus ensured that during a mechanical closing operation mechanical actuation of the locking mechanism is possible even if the motorized drive malfunctions. This arrangement has proven to be successful.
More recently and, in particular, in so-called hood latches, i.e. motor vehicle door latches on a motor vehicle door hood or in the area of the motor vehicle hood, there is a requirement for making a gap between the motor vehicle door or the motor vehicle hood and the motor vehicle body as small as possible and for reducing the gap to 0 mm or nearly 0 mm. This requirement is not only for aesthetical reasons, requiring a smooth and continuous surface in modern motor vehicles. Moreover, the size of the gap has, in particular in this area, a direct effect on the air turbulence in the front area, which depending on its origin and form, can negatively influence air resistance. Convincing solutions have so far been missing in this area. The invention aims to remedy this.